1. Field of the Invention
The present invention relates to a structure having a superhydrophobic and amphiphilic(oleophilic) surface and a fabrication method thereof.
2. Background of the Invention
As the industry is developed, environmental problems have become remarkably obvious, thereby continuously increasing the demand for materials for separating and removing a particular material from a mixed material, such as oily water separation, seawater desalination, and the like. In particular, a lot of studies for separation filter or nonwoven fabric type materials have been carried out, and moreover, studies for performance enhancement in separation materials and applications thereof have been actively implemented. Technologies for separating water and oil from polluted water that is polluted with oil or the like are regarded highly important in the water treatment field. Materials for oily water separation should have a hydrophobic surface to water while at the same time having an amphiphilic(oleophilic) surface to oil.
Polymers such as polyethylene, polystyrene, and the like are primarily used for materials for oily water separation.
Nonwoven fabrics typically have an amphiphilic(oleophilic) and hydrophobic characteristic, but the hydrophobic characteristic (contact angle) thereof is about 100 degrees, and thus additional enhancement of the hydrophobic characteristic may be required for nonwoven fabrics to be used as a material for oily water separation.
In order to be used as a material for oily water separation, preferably, the contact angle to pure water should be 150 degrees or more and the contact angle hysteresis should be 10 degrees or less. Hence, studies for making a superhydrophobic surface having a small contact angle hysteresis like a lotus leaf surface in nature have been carried out. If a solid surface having such a superhydrophobic property is used, then fluid may not be formed on a superhydrophobic surface thereof, and as a result, the surface will be automatically cleaned. Furthermore, it has high usefulness to be used as a channel inner wall surface having a low resistance to fluid and drop flow in a microfluid device.